Now, to the stunning interview with lance armstrong, coming clean to oprah about doping to win. Did he really tell the truth? The whole truth? Abc's neal karlinsky who has covered lance armstrong for years is here with the dramatic details. Reporter: Good morning. It was surreal to watch. This is a man who has fought with everything he could to maintain his lie, through vicious attacks, threats and lawsuits. But last night, lance armstrong came clean, almost as if he decided to flip a switch from somewhere deep inside. I'd like you to walk me through it. Were there, you know, pill deliveries? And blood in secret refrigerators? How did it work? We need a long time. Reporter: Calling himself an arrogant bully, lance armstrong had no good answer to explain away one of the biggest lies all of sport. I'll start my answer by saying, this is too late. I view this situation as one, big lie, that I repeated many times. Reporter: The man who won the tour de France seven times, only to have his titles stripped away, admitted to using a slew of performance-enhancing drug, in such a matter-of-fact way, you would never know he did everything in his power to prosect this secret? Did you ever take performance-enhancing substances to enhance your cycling performance? Yes. Did you ever blood dope or use blood transfusions to enhance your cycling performance? Yes. Reseemed to use the momentum of his own story that he got carried away. You overcome answerer. Did it feel wrong? Scary. Did you feel bad about it? No. Even scarier. Did you feel in any way that you were cheating? No. That's the scariest. Reporter: But he said this interview, his former teammate, floyd landis, coming forward and telling all in an abc news exclusive, was the beginning of the end. Many people think that the real tipping point was floyd landis and his decision to come forward and confess. I'd agree with in a. That was the tipping point? Reporter: What those who know him say was missing, in the words, the body language, in all of it, was any kind of feeling, of contrition. Were you a bully? Yeah. Yeah. I was a bully. I tried to control the narrative. If I didn't like what somebody said, and for whatever reasons in my own head, whether I viewed there as somebody being disloyal or a friend turning on you or whatever, I tried to control that. And say, that's a lie. They're liars. Reporter: Many thought the apologies in particular didn't have much heart to them. And then, of course, there's the question of how much of what he said can really be believed since armstrong clearly admitted to being a very, very good liar, george. That's the bottom line. Neal, thanks very much.

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